Under Drive Pulley

I'm looking to add an under drive water pump pulley to my 07 4.3L engine. Can someone give me a source for purchasing one? I haven't had much luck searching the net for one. I already have the crank and alternator pulleys so I don't need a kit.

Can I ask why you wants smaller water pump or alt pulley? The point of the underdrive crank pulley or to reduce parasitic loss, replacing the other with smaleer pulleys would counter act this andjust make it a bitch to find a proper fitting belt

Can I ask why you wants smaller water pump or alt pulley? The point of the underdrive crank pulley or to reduce parasitic loss, replacing the other with smaleer pulleys would counter act this andjust make it a bitch to find a proper fitting belt

For a crank pulley yes. But if you go changing water pump and alternator pulleys your gonna be defeating the crank pulley and ducking up your belt length.
By going to a smaller pulley on the accessories your actually increasing the Roma of said accessory and adding resistance to the belt that will put more strain on the engine.

I'm looking to add an under drive water pump pulley to my 07 4.3L engine. Can someone give me a source for purchasing one? I haven't had much luck searching the net for one. I already have the crank and alternator pulleys so I don't need a kit.

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What benefit are you hoping for with an underdriven pulley system? I don't see you getting more than a few horse increase from such a system for a 200HP engine.

Guys that have superchargers will put a small pulley on the supercharger to make it spin faster increasing boost.

IMO, an underdriven pulley setup on a stock 4.3L engine is probably a waste of time.